Sen. Scott Brown (R-Mass.) and his Democratic opponent, Elizabeth Warren, are in a statistical tie among likely voters, with a huge swath of the electorate still undecided in this marquee Senate battle, according to a new poll.

A Boston Globe survey found that, in a horserace matchup, 37 percent would vote for Brown, 35 percent would vote for Warren and 26 percent were undecided.

Brown held a substantial lead among self-described independents, with 42 percent telling a pollster they would vote to re-elect him and only 14 percent saying they would cast their ballot for Warren.

Brown remains very well-liked in the Bay State. Fifty-four percent of likely voters held a favorable opinion of him while just 29 percent had an unfavorable opinion. Seven percent didn't know.

Warren, a Harvard Law School professor, consumer advocate and the presumptive Democratic nominee, is less well-known in the commonwealth. Forty-seven percent of likely voters had a favorable opinion of her while just 23 percent had an unfavorable opinion of her. Twenty-five percent didn't know.

When likely voters were asked which candidate best understood people like them, Brown and Warren were statistically tied. But Brown had a substantial edge among independents.

The poll, conducted by the University of New Hampshire Survey Center for the Globe, was in the field from March 21 to 27 and had a margin of error of 4.2 points. The survey used live interviewers calling random landline and cellphone numbers to ask 544 Massachusetts residents who are likely to vote this November about their political leanings.